Octodrilus complanatus (Dugés, 1828)

Description – External – Body length 100 – 270 mm, diameter 4 – 10 mm, 150– 251 segments. Colour dark grey or brownish. Head epilobous, first dorsal pore around intersegmental furrow 12/13. Glandular tumescence usually on 21, 39 ab. Setae widely paired, setal arrangement after the clitellum: aa:ab:bc:cd:dd=4:2:1.6:1:80. Clitellum extends on segments ½ 27, 28, 29 (30) – 37, 38 saddle–shaped. Tubercles as thin bands extend at the margin of the clitellum on 28, 29, 30 – 38, 39, 40, 41. Male pore on 15 between setae b–c, small.

Internal –  Two pairs of testes in 10, 11 segment enclosed in oesophageal testis sacs. Four pairs of vesicles in 9 – 12 and seven pairs of spermathecae in 6/7 – 12/13, open in the setal line c. Calciferous glands in 10 – 12, with lateral diverticula in 10. Last pair of lateral hearts in 11 and a pair small comissures in 12. Crop in 15–16, gizzards in 17–18. Excretory system holonephridial. Nephridial bladders are of ocarina-shaped. Cross section of longitudinal muscle layer is of pinnate type.